staging:iio:dac: Add AD5380 driver

This patch adds support for the Analog Devices D5380, AD5381,
AD5382, AD5383, AD5384, AD5390, AD5391, AD5392 multi-channel
Digital to Analog Converters.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/dac/Kconfig

@@ -24,6 +24,19 @@ config AD5360
 	  To compile this driver as module choose M here: the module will be called
 	  ad5360.
 
+config AD5380
+	tristate "Analog Devices AD5380/81/82/83/84/90/91/92 DAC driver"
+	depends on (SPI_MASTER || I2C)
+	select REGMAP_I2C if I2C
+	select REGMAP_SPI if SPI_MASTER
+	help
+	  Say yes here to build support for Analog Devices AD5380, AD5381,
+	  AD5382, AD5383, AD5384, AD5390, AD5391, AD5392 multi-channel
+	  Digital to Analog Converters (DAC).
+
+	  To compile this driver as module choose M here: the module will be called
+	  ad5380.
+
 config AD5421
 	tristate "Analog Devices AD5421 DAC driver"
 	depends on SPI

drivers/staging/iio/dac/Makefile

@@ -3,6 +3,7 @@
 #
 
 obj-$(CONFIG_AD5360) += ad5360.o
+obj-$(CONFIG_AD5380) += ad5380.o
 obj-$(CONFIG_AD5421) += ad5421.o
 obj-$(CONFIG_AD5624R_SPI) += ad5624r_spi.o
 obj-$(CONFIG_AD5064) += ad5064.o

drivers/staging/iio/dac/ad5380.c

@@ -0,0 +1,676 @@
+/*
+ * Analog devices AD5380, AD5381, AD5382, AD5383, AD5390, AD5391, AD5392
+ * multi-channel Digital to Analog Converters driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+#include "dac.h"
+
+
+#define AD5380_REG_DATA(x)	(((x) << 2) | 3)
+#define AD5380_REG_OFFSET(x)	(((x) << 2) | 2)
+#define AD5380_REG_GAIN(x)	(((x) << 2) | 1)
+#define AD5380_REG_SF_PWR_DOWN	(8 << 2)
+#define AD5380_REG_SF_PWR_UP	(9 << 2)
+#define AD5380_REG_SF_CTRL	(12 << 2)
+
+#define AD5380_CTRL_PWR_DOWN_MODE_OFFSET	13
+#define AD5380_CTRL_INT_VREF_2V5		BIT(12)
+#define AD5380_CTRL_INT_VREF_EN			BIT(10)
+
+/**
+ * struct ad5380_chip_info - chip specific information
+ * @channel_template:	channel specification template
+ * @num_channels:	number of channels
+ * @int_vref:		internal vref in uV
+*/
+
+struct ad5380_chip_info {
+	struct iio_chan_spec	channel_template;
+	unsigned int		num_channels;
+	unsigned int		int_vref;
+};
+
+/**
+ * struct ad5380_state - driver instance specific data
+ * @regmap:		regmap instance used by the device
+ * @chip_info:		chip model specific constants, available modes etc
+ * @vref_reg:		vref supply regulator
+ * @vref:		actual reference voltage used in uA
+ * @pwr_down:		whether the chip is currently in power down mode
+ */
+
+struct ad5380_state {
+	struct regmap			*regmap;
+	const struct ad5380_chip_info	*chip_info;
+	struct regulator		*vref_reg;
+	int				vref;
+	bool				pwr_down;
+};
+
+enum ad5380_type {
+	ID_AD5380_3,
+	ID_AD5380_5,
+	ID_AD5381_3,
+	ID_AD5381_5,
+	ID_AD5382_3,
+	ID_AD5382_5,
+	ID_AD5383_3,
+	ID_AD5383_5,
+	ID_AD5390_3,
+	ID_AD5390_5,
+	ID_AD5391_3,
+	ID_AD5391_5,
+	ID_AD5392_3,
+	ID_AD5392_5,
+};
+
+#define AD5380_CHANNEL(_bits) {					\
+	.type = IIO_VOLTAGE,					\
+	.indexed = 1,						\
+	.output = 1,						\
+	.info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT |		\
+		IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT |		\
+		IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT,		\
+	.scan_type = IIO_ST('u', (_bits), 16, 14 - (_bits))	\
+}
+
+static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
+	[ID_AD5380_3] = {
+		.channel_template = AD5380_CHANNEL(14),
+		.num_channels = 40,
+		.int_vref = 1250000,
+	},
+	[ID_AD5380_5] = {
+		.channel_template = AD5380_CHANNEL(14),
+		.num_channels = 40,
+		.int_vref = 2500000,
+	},
+	[ID_AD5381_3] = {
+		.channel_template = AD5380_CHANNEL(12),
+		.num_channels = 16,
+		.int_vref = 1250000,
+	},
+	[ID_AD5381_5] = {
+		.channel_template = AD5380_CHANNEL(12),
+		.num_channels = 16,
+		.int_vref = 2500000,
+	},
+	[ID_AD5382_3] = {
+		.channel_template = AD5380_CHANNEL(14),
+		.num_channels = 32,
+		.int_vref = 1250000,
+	},
+	[ID_AD5382_5] = {
+		.channel_template = AD5380_CHANNEL(14),
+		.num_channels = 32,
+		.int_vref = 2500000,
+	},
+	[ID_AD5383_3] = {
+		.channel_template = AD5380_CHANNEL(12),
+		.num_channels = 32,
+		.int_vref = 1250000,
+	},
+	[ID_AD5383_5] = {
+		.channel_template = AD5380_CHANNEL(12),
+		.num_channels = 32,
+		.int_vref = 2500000,
+	},
+	[ID_AD5390_3] = {
+		.channel_template = AD5380_CHANNEL(14),
+		.num_channels = 16,
+		.int_vref = 1250000,
+	},
+	[ID_AD5390_5] = {
+		.channel_template = AD5380_CHANNEL(14),
+		.num_channels = 16,
+		.int_vref = 2500000,
+	},
+	[ID_AD5391_3] = {
+		.channel_template = AD5380_CHANNEL(12),
+		.num_channels = 16,
+		.int_vref = 1250000,
+	},
+	[ID_AD5391_5] = {
+		.channel_template = AD5380_CHANNEL(12),
+		.num_channels = 16,
+		.int_vref = 2500000,
+	},
+	[ID_AD5392_3] = {
+		.channel_template = AD5380_CHANNEL(14),
+		.num_channels = 8,
+		.int_vref = 1250000,
+	},
+	[ID_AD5392_5] = {
+		.channel_template = AD5380_CHANNEL(14),
+		.num_channels = 8,
+		.int_vref = 2500000,
+	},
+};
+
+static ssize_t ad5380_read_dac_powerdown(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad5380_state *st = iio_priv(indio_dev);
+
+	return sprintf(buf, "%d\n", st->pwr_down);
+}
+
+static ssize_t ad5380_write_dac_powerdown(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad5380_state *st = iio_priv(indio_dev);
+	bool pwr_down;
+	int ret;
+
+	ret = strtobool(buf, &pwr_down);
+	if (ret)
+		return ret;
+
+	mutex_lock(&indio_dev->mlock);
+
+	if (pwr_down)
+		ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_DOWN, 0);
+	else
+		ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_UP, 0);
+
+	st->pwr_down = pwr_down;
+
+	mutex_unlock(&indio_dev->mlock);
+
+	return ret ? ret : len;
+}
+
+static IIO_DEVICE_ATTR(out_voltage_powerdown,
+			S_IRUGO | S_IWUSR,
+			ad5380_read_dac_powerdown,
+			ad5380_write_dac_powerdown, 0);
+
+static const char ad5380_powerdown_modes[][15] = {
+	[0]	= "100kohm_to_gnd",
+	[1]	= "three_state",
+};
+
+static ssize_t ad5380_read_powerdown_mode(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad5380_state *st = iio_priv(indio_dev);
+	unsigned int mode;
+	int ret;
+
+	ret = regmap_read(st->regmap, AD5380_REG_SF_CTRL, &mode);
+	if (ret)
+		return ret;
+
+	mode = (mode >> AD5380_CTRL_PWR_DOWN_MODE_OFFSET) & 1;
+
+	return sprintf(buf, "%s\n", ad5380_powerdown_modes[mode]);
+}
+
+static ssize_t ad5380_write_powerdown_mode(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad5380_state *st = iio_priv(indio_dev);
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < ARRAY_SIZE(ad5380_powerdown_modes); ++i) {
+		if (sysfs_streq(buf, ad5380_powerdown_modes[i]))
+			break;
+	}
+
+	if (i == ARRAY_SIZE(ad5380_powerdown_modes))
+		return -EINVAL;
+
+	ret = regmap_update_bits(st->regmap, AD5380_REG_SF_CTRL,
+		1 << AD5380_CTRL_PWR_DOWN_MODE_OFFSET,
+		i << AD5380_CTRL_PWR_DOWN_MODE_OFFSET);
+
+	return ret ? ret : len;
+}
+
+static IIO_DEVICE_ATTR(out_voltage_powerdown_mode,
+			S_IRUGO | S_IWUSR,
+			ad5380_read_powerdown_mode,
+			ad5380_write_powerdown_mode, 0);
+
+static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
+			"100kohm_to_gnd three_state");
+
+static struct attribute *ad5380_attributes[] = {
+	&iio_dev_attr_out_voltage_powerdown.dev_attr.attr,
+	&iio_dev_attr_out_voltage_powerdown_mode.dev_attr.attr,
+	&iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad5380_attribute_group = {
+	.attrs = ad5380_attributes,
+};
+
+static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
+	long info)
+{
+	switch (info) {
+	case 0:
+		return AD5380_REG_DATA(chan->address);
+	case IIO_CHAN_INFO_CALIBBIAS:
+		return AD5380_REG_OFFSET(chan->address);
+	case IIO_CHAN_INFO_CALIBSCALE:
+		return AD5380_REG_GAIN(chan->address);
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int ad5380_write_raw(struct iio_dev *indio_dev,
+	struct iio_chan_spec const *chan, int val, int val2, long info)
+{
+	const unsigned int max_val = (1 << chan->scan_type.realbits);
+	struct ad5380_state *st = iio_priv(indio_dev);
+
+	switch (info) {
+	case 0:
+	case IIO_CHAN_INFO_CALIBSCALE:
+		if (val >= max_val || val < 0)
+			return -EINVAL;
+
+		return regmap_write(st->regmap,
+			ad5380_info_to_reg(chan, info),
+			val << chan->scan_type.shift);
+	case IIO_CHAN_INFO_CALIBBIAS:
+		val += (1 << chan->scan_type.realbits) / 2;
+		if (val >= max_val || val < 0)
+			return -EINVAL;
+
+		return regmap_write(st->regmap,
+			AD5380_REG_OFFSET(chan->address),
+			val << chan->scan_type.shift);
+	default:
+		break;
+	}
+	return -EINVAL;
+}
+
+static int ad5380_read_raw(struct iio_dev *indio_dev,
+	struct iio_chan_spec const *chan, int *val, int *val2, long info)
+{
+	struct ad5380_state *st = iio_priv(indio_dev);
+	unsigned long scale_uv;
+	int ret;
+
+	switch (info) {
+	case 0:
+	case IIO_CHAN_INFO_CALIBSCALE:
+		ret = regmap_read(st->regmap, ad5380_info_to_reg(chan, info),
+					val);
+		if (ret)
+			return ret;
+		*val >>= chan->scan_type.shift;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_CALIBBIAS:
+		ret = regmap_read(st->regmap, AD5380_REG_OFFSET(chan->address),
+					val);
+		if (ret)
+			return ret;
+		*val >>= chan->scan_type.shift;
+		val -= (1 << chan->scan_type.realbits) / 2;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		scale_uv = ((2 * st->vref) >> chan->scan_type.realbits) * 100;
+		*val =  scale_uv / 100000;
+		*val2 = (scale_uv % 100000) * 10;
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info ad5380_info = {
+	.read_raw = ad5380_read_raw,
+	.write_raw = ad5380_write_raw,
+	.attrs = &ad5380_attribute_group,
+	.driver_module = THIS_MODULE,
+};
+
+static int __devinit ad5380_alloc_channels(struct iio_dev *indio_dev)
+{
+	struct ad5380_state *st = iio_priv(indio_dev);
+	struct iio_chan_spec *channels;
+	unsigned int i;
+
+	channels = kcalloc(sizeof(struct iio_chan_spec),
+			st->chip_info->num_channels, GFP_KERNEL);
+
+	if (!channels)
+		return -ENOMEM;
+
+	for (i = 0; i < st->chip_info->num_channels; ++i) {
+		channels[i] = st->chip_info->channel_template;
+		channels[i].channel = i;
+		channels[i].address = i;
+	}
+
+	indio_dev->channels = channels;
+
+	return 0;
+}
+
+static int __devinit ad5380_probe(struct device *dev, struct regmap *regmap,
+	enum ad5380_type type, const char *name)
+{
+	struct iio_dev *indio_dev;
+	struct ad5380_state *st;
+	unsigned int ctrl = 0;
+	int ret;
+
+	indio_dev = iio_allocate_device(sizeof(*st));
+	if (indio_dev == NULL) {
+		dev_err(dev, "Failed to allocate iio device\n");
+		ret = -ENOMEM;
+		goto error_regmap_exit;
+	}
+
+	st = iio_priv(indio_dev);
+	dev_set_drvdata(dev, indio_dev);
+
+	st->chip_info = &ad5380_chip_info_tbl[type];
+	st->regmap = regmap;
+
+	indio_dev->dev.parent = dev;
+	indio_dev->name = name;
+	indio_dev->info = &ad5380_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->num_channels = st->chip_info->num_channels;
+
+	ret = ad5380_alloc_channels(indio_dev);
+	if (ret) {
+		dev_err(dev, "Failed to allocate channel spec: %d\n", ret);
+		goto error_free;
+	}
+
+	if (st->chip_info->int_vref == 2500000)
+		ctrl |= AD5380_CTRL_INT_VREF_2V5;
+
+	st->vref_reg = regulator_get(dev, "vref");
+	if (!IS_ERR(st->vref_reg)) {
+		ret = regulator_enable(st->vref_reg);
+		if (ret) {
+			dev_err(dev, "Failed to enable vref regulators: %d\n",
+				ret);
+			goto error_free_reg;
+		}
+
+		st->vref = regulator_get_voltage(st->vref_reg);
+	} else {
+		st->vref = st->chip_info->int_vref;
+		ctrl |= AD5380_CTRL_INT_VREF_EN;
+	}
+
+	ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl);
+	if (ret) {
+		dev_err(dev, "Failed to write to device: %d\n", ret);
+		goto error_disable_reg;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		dev_err(dev, "Failed to register iio device: %d\n", ret);
+		goto error_disable_reg;
+	}
+
+	return 0;
+
+error_disable_reg:
+	if (!IS_ERR(st->vref_reg))
+		regulator_disable(st->vref_reg);
+error_free_reg:
+	if (!IS_ERR(st->vref_reg))
+		regulator_put(st->vref_reg);
+
+	kfree(indio_dev->channels);
+error_free:
+	iio_free_device(indio_dev);
+error_regmap_exit:
+	regmap_exit(regmap);
+
+	return ret;
+}
+
+static int __devexit ad5380_remove(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad5380_state *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	kfree(indio_dev->channels);
+
+	if (!IS_ERR(st->vref_reg)) {
+		regulator_disable(st->vref_reg);
+		regulator_put(st->vref_reg);
+	}
+
+	regmap_exit(st->regmap);
+	iio_free_device(indio_dev);
+
+	return 0;
+}
+
+static bool ad5380_reg_false(struct device *dev, unsigned int reg)
+{
+	return false;
+}
+
+static const struct regmap_config ad5380_regmap_config = {
+	.reg_bits = 10,
+	.val_bits = 14,
+
+	.max_register = AD5380_REG_DATA(40),
+	.cache_type = REGCACHE_RBTREE,
+
+	.volatile_reg = ad5380_reg_false,
+	.readable_reg = ad5380_reg_false,
+};
+
+#if IS_ENABLED(CONFIG_SPI_MASTER)
+
+static int __devinit ad5380_spi_probe(struct spi_device *spi)
+{
+	const struct spi_device_id *id = spi_get_device_id(spi);
+	struct regmap *regmap;
+
+	regmap = regmap_init_spi(spi, &ad5380_regmap_config);
+
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
+}
+
+static int __devexit ad5380_spi_remove(struct spi_device *spi)
+{
+	return ad5380_remove(&spi->dev);
+}
+
+static const struct spi_device_id ad5380_spi_ids[] = {
+	{ "ad5380-3", ID_AD5380_3 },
+	{ "ad5380-5", ID_AD5380_5 },
+	{ "ad5381-3", ID_AD5381_3 },
+	{ "ad5381-5", ID_AD5381_5 },
+	{ "ad5382-3", ID_AD5382_3 },
+	{ "ad5382-5", ID_AD5382_5 },
+	{ "ad5383-3", ID_AD5383_3 },
+	{ "ad5383-5", ID_AD5383_5 },
+	{ "ad5384-3", ID_AD5380_3 },
+	{ "ad5384-5", ID_AD5380_5 },
+	{ "ad5390-3", ID_AD5390_3 },
+	{ "ad5390-5", ID_AD5390_5 },
+	{ "ad5391-3", ID_AD5391_3 },
+	{ "ad5391-5", ID_AD5391_5 },
+	{ "ad5392-3", ID_AD5392_3 },
+	{ "ad5392-5", ID_AD5392_5 },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
+
+static struct spi_driver ad5380_spi_driver = {
+	.driver = {
+		   .name = "ad5380",
+		   .owner = THIS_MODULE,
+	},
+	.probe = ad5380_spi_probe,
+	.remove = __devexit_p(ad5380_spi_remove),
+	.id_table = ad5380_spi_ids,
+};
+
+static inline int ad5380_spi_register_driver(void)
+{
+	return spi_register_driver(&ad5380_spi_driver);
+}
+
+static inline void ad5380_spi_unregister_driver(void)
+{
+	spi_unregister_driver(&ad5380_spi_driver);
+}
+
+#else
+
+static inline int ad5380_spi_register_driver(void)
+{
+	return 0;
+}
+
+static inline void ad5380_spi_unregister_driver(void)
+{
+}
+
+#endif
+
+#if IS_ENABLED(CONFIG_I2C)
+
+static int __devinit ad5380_i2c_probe(struct i2c_client *i2c,
+	const struct i2c_device_id *id)
+{
+	struct regmap *regmap;
+
+	regmap = regmap_init_i2c(i2c, &ad5380_regmap_config);
+
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	return ad5380_probe(&i2c->dev, regmap, id->driver_data, id->name);
+}
+
+static int __devexit ad5380_i2c_remove(struct i2c_client *i2c)
+{
+	return ad5380_remove(&i2c->dev);
+}
+
+static const struct i2c_device_id ad5380_i2c_ids[] = {
+	{ "ad5380-3", ID_AD5380_3 },
+	{ "ad5380-5", ID_AD5380_5 },
+	{ "ad5381-3", ID_AD5381_3 },
+	{ "ad5381-5", ID_AD5381_5 },
+	{ "ad5382-3", ID_AD5382_3 },
+	{ "ad5382-5", ID_AD5382_5 },
+	{ "ad5383-3", ID_AD5383_3 },
+	{ "ad5383-5", ID_AD5383_5 },
+	{ "ad5384-3", ID_AD5380_3 },
+	{ "ad5384-5", ID_AD5380_5 },
+	{ "ad5390-3", ID_AD5390_3 },
+	{ "ad5390-5", ID_AD5390_5 },
+	{ "ad5391-3", ID_AD5391_3 },
+	{ "ad5391-5", ID_AD5391_5 },
+	{ "ad5392-3", ID_AD5392_3 },
+	{ "ad5392-5", ID_AD5392_5 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ad5380_i2c_ids);
+
+static struct i2c_driver ad5380_i2c_driver = {
+	.driver = {
+		   .name = "ad5380",
+		   .owner = THIS_MODULE,
+	},
+	.probe = ad5380_i2c_probe,
+	.remove = __devexit_p(ad5380_i2c_remove),
+	.id_table = ad5380_i2c_ids,
+};
+
+static inline int ad5380_i2c_register_driver(void)
+{
+	return i2c_add_driver(&ad5380_i2c_driver);
+}
+
+static inline void ad5380_i2c_unregister_driver(void)
+{
+	i2c_del_driver(&ad5380_i2c_driver);
+}
+
+#else
+
+static inline int ad5380_i2c_register_driver(void)
+{
+	return 0;
+}
+
+static inline void ad5380_i2c_unregister_driver(void)
+{
+}
+
+#endif
+
+static int __init ad5380_spi_init(void)
+{
+	int ret;
+
+	ret = ad5380_spi_register_driver();
+	if (ret)
+		return ret;
+
+	ret = ad5380_i2c_register_driver();
+	if (ret) {
+		ad5380_spi_unregister_driver();
+		return ret;
+	}
+
+	return 0;
+}
+module_init(ad5380_spi_init);
+
+static void __exit ad5380_spi_exit(void)
+{
+	ad5380_i2c_unregister_driver();
+	ad5380_spi_unregister_driver();
+
+}
+module_exit(ad5380_spi_exit);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
+MODULE_LICENSE("GPL v2");